Hi TI experts,
Below is a part of UCD3138 schematic ,I measured the point 2 to AGND when PSU was not working(I used DC source to instead of aux flyback to supply IC used power) ,but waveform shows these is a constant frequency dip in there ,frequency is 22k Hz,does any expert can tell us
ADC channel used : 12
ADC sample rate : 268ks/sec
1.what's that?
2.what does it cause?
3.Is that noise real?
4.Is it ADC cross-talk?
5.How to prevent this ?
6.Does it impact power control performance?
thanks.
If remove RA315 , and measured the AD08 to AGND ,it shows
